Electric floor polishing machine



June 28, 1932. w, MCGEE "1,865,032

ELECTRIC FLOOR POLISHING MACHINE Original Filed Feb. 6, 1929 IIVYENTURmil/Q2112 Z. 7115' Gee.

Patented June 28, 1932 PATENT OFFICE WILLIAM L. M GGEE, 0F MEDIA,.PENNSYLVANIA ELECTRIC FLOOR IOLISHING MACHINE Original applicationfiled February 6, 1929, Serial No. 337,783.

1930. Serial This invention relates to floor polishing machines, andmore particularly to a machine wherein a pair of circular disk-likebrushes, rubbers, polishing or abrading disks, rotatable upon averticalaxis forming the support upon which the machine rests or is supportedwhen the machine is in operation, and the present invention relates moreparticularly to the provision of means whereby brushes may beinterchangeably secured to the ends of the spindles irrespective ofthedirection in which the brushes are rotated.

This invention is fully shown and described in a copending application,Serial Number 337,783, filed by me in the United States Patent Ofiioe,February 6, 1929, of which this application is a division.

One object of this invention is to provide a device for attaching thebrushes to the spindies by Which they are carried and rotated, saidarrangement being very simple in construction and easily operatedwithout 'mechanical complications, so that it is merely necessary forthe user, in order to remove a brush, to pull it straight off the end ofthe shaft against a.relatively slight resistance, and for one to attacha brush to the shaft to merely be required to slip or slide the brushover the lower end of the shaft.

A further object of this invention is to en able the housewife to removeone set of brushes and to replace them With another similar set ofbrushes or tools, dependent upon the use to which the machine is to beput, all said tools being easily attached to either spindle irrespectiveof the direction in which the spindle is rotated by the driving motor.

A further object of this invention is to pro vide a telescopingconnection between the ends of the drive shafts and brushes connectedthereto, and to dispense with any screwthreaded connection whereby thebrushes may be easily slipped 011 over the ends of either spindle andare removably locked thereon in driving engagement therewith.

A further object of my invention is to provide the telescoping parts ofthe brush shafts and brush sockets with a locking device com- Dividedand this application filed March 20, No. 437,329.

prising a depressible member in one part, spring pressed toward theother part and seated in a transverse groove of said other part when thebrush and shaft are locked in engagement with each other.

A further object of this invention is to provide the groove, in one ofsaid members above referred to, with a rounded edge over which therounded end of the plunger may be readily slid in removing the brushfrom the shaft and by which the depression of the plunger against thetension of the spring is facilitated.

Further objectsof this invention will appear in the specification andclaims below.

It is to be noted that the floor polishing machine, with which thepresent invention is particularly adapted to be used, is one providedwith two brushes rotated in opposite directions, the brushes beingprovided with identic devices for securing them to the shafts. For thepurpose of the present disclosure, however, but one of the brushes ofthe two shown in my copending application is illustrated in the drawing.

Referring now to the drawing forming a part of this specification and inwhich the same reference characters are used throughout the variousviews to designate the same parts,

Fig. 1 is a vertical section through a floor polishing machine andthrough the axis of one of the brushes.

Fig. 2 is a horizontal sectional view on the line 22 of Fig. 1. v

Fig. 3 is an enlarged sectional View of a portion of a brushshaft and asocket sleeve, the unitary locking member, the locking plunger thereof,and clearly disclosing the shape of the upper part of the Wall of thegroove which is rounded to facilitate the removal of the brush.

Fig. 4 is a fragmentary vertical axialsection of a slightly modifiedconstruction for looking a brush to the end. of a shaft, and

Fig. 5 is a horizontal cross-sectional view on the line 5-5 of Fig. 4.

My floor polishing machine comprises a casing or housing 1, providedwith a chamber 2in which is mounted the electric motor preferably use a(not shown) upon a drive shaft 3, suitably journaled in the housing 1.On opposite sides of the chamber 2 and on the shaft 3 are worms 4 (butone is shown in the drawing), each meshing with a worm gear 5 mounted onthe upper ends of a brush shaft 6, preferably mounted to turn in a pairof spaced bearings 7, 7 forced into and permanently frictionally held inthe upper and lower ends respectively of the cylindrical chamber 8. Thespace between the two alined bearings 7, 7 constitutes a chamber inwhich I preferably place absorbent material, such as felt washers 9, toretain any lubricant which might work into the chamber and from thechamber leak to the floor through the lower bearing 7. Below this lowerbearing 7, the brush shaft 6 is preferably provided with a flange 10,and below said flange with a brush engaging end 11 which, in the form ofmy invention illustrated in Figs. 1 and 2, is preferably polygonalintransverse cross-section.

I preferably make the end 11 substantia-lly square in transversecross-section, but the vertical edges 12 between adjacent flat surfacesare preferably rounded. The squared end 11 is adapted to slide easilylongitudinally into a similarly shaped socket hole 13 in a socketbushing 14 attached to the upper side of a circular brush 15 as byscrews 16 passing through the flange 17 of said bushing 14. The socketbushing 14 referably fits into a hole 18 passing through the back 19 ofthe brush 15 vertically at the center thereof, and the lower end ofthesocket bush-ing 14 is provided with a rigid loop20 approximatelysemicircular in shape, extending downwardly into a conical recess 21 onthe underside of the back of the brush so that an operator may" readilyinvert the housing, insert a finger through the loop 20 and easily drawthe brush 15 off from the squared end 11 on the shaft 6, by exertingajerk on the loop.

The brush 15 is provided with a plurality of rows or tiers or bunches ofbristles 22, by which the weight of the entire mechanism is supported onthe floor.

One ofthe surfaces of the interlocking portions of the shaft and of thesocket sleeves as,

for-instance, a surface 11 of the shaft, is provided with a plunger 23which is spring pressed toward a coacting surface 14 of the interlockingportion of the bushing 14. I locking device which is a unit 24,.comprising the said plunger 23 having a preferably spherical outer end,housed in and normally held projectingwell beyond the otherwise open endof a cartridge shaped shell 25 by a spring 26, surrounding a rear-Wardly extending plunger rod 27 unitary with the plunger 23 andprojecting-through a small opening in the rear closed end 28 of theshell. Saidplunger rod 27 is provided with ahead 29- outside of theclosed end 28 to restrain the outward or forward movement of the plungerbeyond a predetermined point. This unitary locking device 24 ispreferably inserted into a hole 30 drilled into the squared end 11 ofthe shaft 6 deeper than the over-all dimension of the plunger 23, rod 27and head 29 by at least the amount that the plunger 23 projects abovethe surface 11*.

The surface of the other coacting portions of the sleeve and shaft, andpreferably the surface 31 of the hole 13, are provided with alinedgrooves 31 or under-cuts, one on each surface 31. When, therefore, abrush is slipped over the squared end 11 of the shaft 6 and pressedtoward the collar or flange 17, the plunger head 23 will first beengaged by the taper surface 31 at the upper end of the hole 13 and willbe depressed intothe shell 25 and sliding over the shoulder 31, willslide down over the reversely curved and tapered surface 31 into thedeepest part of the groove 31 in which position the upper end of thebushing 14 will be seated upon the flange 10.

The pressure of the spring 26 on the plunger 23 when the latter is thusseated in the recess or groove 31, as shown in Fig. 3, is made amplysufficient to retain the brushes securely on the ends of the shaft 6whenever the device, as a whole, is lifted from the floor.

In order, however, that there may be no difficulty in removing thebrushes from the shaft 6, I preferably make the upper wall 31 in theform of a reverse curve axially of the bushing, so that the surface 3-1will have a camming action on the spherical end of the plunger 23 andeasily depress said plunger into its shell 25 against the tension of thespring 26 by the application of a sharp tug or pull on the loop 20 ofthe socket sleeve or bushing 14 with the four walls or surfaces 31 ofthe socket hole 13, thus provided with undercut grooves 31 in the mannerabove described: no care is required to be exercised in placing thebrush on the end of a shaft. As soon as the brush is turned to bring aflat side 13- of a hole 13 against a flat surface 11 on the end of thebrush shaft, the brush may be easily slipped over the end 11 of thebrush shaft into locking position and the plunger will project into thegroove 31 with which the wall acent thereto is provided.

Heretofore it has been deemed necessary to provide the endsof the brushshafts with right and left-hand screws, but that precludes anyinterchange of brushes from the right to the left-hand side of themachine and vice versa, and requires the operator to know which way abrush must be rotated to take the brush off or put it on the end of ashaft. By my improvement, such conditions are avoided. Any ofthe-brushes which can be used inmy device are'capableof being easilyslipped over the end of either shaft which fits into a similar polygonalhole 13 in the brush. And to remove the-brush, one merely applies asharp tug or jerk to the bail or loop 20 at the middle of the brush andthe brush is easily removed from the end of the shaft.

In Figs. 4 and 5 the lower end 111 of the shaft 6 is cylindrical andfits into a cylindrical hole 113 in the bushing 114. The end, 111 isprovided with a cross-pin 111 the projecting ends of which fit intonotches 113 in the top edge of the bushing 114. The inner surface of thehole 113 is provided with an annular groove 131 and the tapering surface113 at the upper end of the hole and the reversely curved wall 131 allto coact with the spring pressed plunger 23, as above described inconnection with Figs. 1 to 3 inelusive.

I have also shown the loop or bail 120 as separate from the sleeve 114and having its ends fitting against the wall of the conical recesses 21and secured in place by screws 116 passing through the ends of the loop120 and through the back 119 and riveted into the flange 17.

There are certain advantages to this construction. The brushes arepossibly more easily slip ed over a cylindrical end of a brush shaf tthan over a polygonal one; no obstruction, such as an integral loop orbail is present to interfere with the free access to the interior of thehole from either end of the bushing before the loop is attached, therebyfacilitating the mechanical operation of undercutting the hole orproviding it with a groove 131 to cooperate with the plunger 23. Theoperation is precisely the same as above described, in that the brushesmay he slipped over the lower end of either shaft irrespective of thedirection of its rotation and into driving engagement therewith and inthat the brushes are easily removed by pulling on the loo I-Iaving thusdescribed my invention, what I claim and desire to protect by LettersPatent of the United States is:

1. In a floor polishing machine having a vertical power driven shaft anda circular polishing member adapted to rest on the floor and to rotateupon a Vertical axis, the combination of means to detachably connectsaid polishing member to said shaft comprising an axial socket in saidpolishing member into which the lower end of said shaft fits and isslidable longitudinally, the shape of said end of said shaft and of saidsocket in transverse cross-section being such as to preclude anyrelative rotation of said shaft with respect to said polishing member,said end of said shaft and said socket forming clutch members, thesurface of one of said clutch members being provided with a springpressed plunger normally held projecting from said surface, and thesurface of the other of said members being provided with a transversegroove into which said plunger catches when said polishing member isslipped over and slid longitudinally on said shaft. V a p 2.1 I11 afloorpolishing. machine havinga gvertical power driven shaftand a circularpolishing member adapted to rest on.the"- floor and to rotate on a vvertical axis, the

combination of means to detachably connect .said polishing memberctosaid shaft, said means, comprisingtelescoping members, one of sa dtelescoping members beingintegral with said shaft and the other integralwith said polishing member, one of the telescoping surfaces of one ofsaidmembers being provided w th a sprmg pressed plunger normally heldyieldingly projecting outwardly from said surface and the coactingsurface of the other of said members being provided with a transversegroove in which said plunger is seated when said polishing member isslipped longitudinally of said shaft to bring said plunger inregistration therewith, the edge of the wall of said groove over whichsaid plunger slides in coming into registration with said groove beingrounded to force said plunger out of said groove when said' polishingmember is removed from or replaced on the end of said shaft.

3. In a floor polishing machine, having a vertical power driven shaftand a circular polishing member adapted to rest on the.

floor and to rotate on a vertical axis, the combination of interlockingmeans to detachably lock said polishing member to said shaft andcomprising two members, one of said members being the lower end of saidshaft lngly projecting from said surface and all the other telescopingsurfaces of the other of said' clutch members being provided with liketransverse grooves in any one of which said plunger is adapted to catchwhen the polishing member is slipped over and slid longitudinally ontosaid shaft.

4. In a floor polishing machine, having a vertical power driven shaftand a circular polishing member adapted to rest on the floor and torotate on a vertical axis, the combination of means to said polishingmember to said shaft and comprising the lower end of said shaft which ispolygonal in transverse cross-section and a socket member having anaxial socket therein into which said polygonal end of said shaft isslidable telescopically and fits, said polygonal end and said socketmember forming clutch members, one of the flat telescoping surfaces ofone of said clutch members being provided with a spring pressed plungl'forming clutch detachably secure i or having a rounded end normall' holdyieldingly projecting from said Suifi ace and all the other flattelescoping surfaces of the other of said clutch members being providedwith a. transverse groove in which said plunger catches when the bi'ushis slipijed over and slid; longitudinally onto said shaft, the edge ofone wall of each of said grooves boing rounded to depress said plungerin drawing said polishing member off and replacing it on the end of saidshaft In Witness whereof, I have herguiit-St my hand this 17th day'ofMarch, 1939; WILLIAM L.

